I installed boost dev tools through apt-get. Then I built boost myself. So to get rid of those dev tools, I did:
apt-get purge libboost*
I saw icons disappear off my screen one by one. The top bar disappeared, seems nearly everything in Ubuntu uses Boost. I should have removed libboost-all-dev.
Is there any way I can fix this mistake, or do I have to reinstall Ubuntu from scratch again?
Do you still have a console? Examine the outputs from your last commands, or see less /var/log/apt/history.log (if that's not meaningful, go hardcore with less /var/log/dpkg.log), and then reinstall what you removed.
apt-get install aptitude
apt would have warned you if you did try to remove something essential, so the worst thing that could happen is that you are forced to reinstall everything you just removed before having your system in a status similar to that before.
warning though: If you uninstalled some system service you made special configurations to, then just reinstalling it will wipe your chances of recovering those old config files you just purged. If you need such, you need to take a far more elaborate approach - on a different system.
